Atacama Humanoid Is Human, Researchers Say

The tiny humanoid discovered in Chile's Atacama Desert in 2003 is a human being, not an alien, researchers have concluded. The six-inch skeleton, nicknamed "Ata," was thought by some to be proof of extraterrestrial life, but Garry Nolan, a microbiology professor at Stanford School of Medicine, said his study of the skeleton shows it to be human, reports LiveScience.

"Every nucleotide I've been able to look at is human," Nolan told LiveScience. "I've only scratched the surface of the analysis, but there is nothing that jumps out so far as to scream 'nonhuman.'" Nolan and his team photographed the skeleton in high resolution, conducted X-ray and CT scans, and sequenced its DNA in the fall of 2012. While they don't yet know what kinds of mutations caused the skeleton's deformities - the elongated skull and unusual number of ribs, as well as the small size - the tests suggest the individual was between six and eight years old when he or she died.

An analysis of the mitochondrial DNA suggests the mother was "an indigenous woman from the Chilean region of South America," Nolan wrote in an email to LiveScience. About 91 percent of the skeleton's total genes match up with the reference human genome, added LiveScience. The mismatches in the other 9 percent could be accounted for in various ways, including DNA degradation in the skeleton.

"It's an interesting medical mystery of an unfortunate human with a series of birth defects that currently the genetics of which are not obvious," wrote Nolan.

The findings were publicized in a crowd-funded documentary called "Sirius," which premiered on April 22.